Hi Vedha
I think it might be to do with quantity? I know that ずつ is used after a quantifier e.g.
私は毎日漢字五つずつお覚える 'I learn 5 kanji every day'
whereas ごとに you can use after a regular noun:
正月は家ごとに角松を立てる・しょうがつはいえごとにかどまつをたてる
'They put up pine tree decorations at every house on New Year's Day.'
I know thatずつ emphasises the 'equal distribution' of the event as well, I'm not sure thatごとに does that.
Maybe add the kanji for it, since some people used that in their example, even though it's rarely used? I never knew that 毎 could be read as ごと and was confused for a moment.
This is a few months late but ごとに can be used after a verb.
ex. なんか日を追うごとに、傷が増えていってないか。
With every day that passes, it seems like you come home with a new injury.
nihongo-c.co.jp/blog/blog-entry-112.html So, this is pretty interesting. If the time before it is in seconds, minutes, or hours, they are the same. If it is in days, months, years, they are different. With these longer times, ごとに means what you'd expect it to. However, おき means that time is placed (おく) in between the two events. 一日おきに means A, then 1 day, then B. 3年おきに means A, then 3 years passes, then B.
This construction can also be used "spacially", as in "木村さんは合う人ごとに挨拶している。", Mr. Kimura greets every person he meets. See A Dictionary of Basic Japanese Grammar.
This is already reflected in some of the quizing questions, and should be updated here.
the grammar point says "A can be a span of time, distance, or situation" but the construction scheme only show the first 2, the "situation" is not in there :) Or, it could have the noun+ごとに, ad in the example above 合う人ごとに
I think situation would fit under "verb" - I try to use the types of speech as much as possible, but in certain situations, I think it makes more sense to go further and specify what type of thing. I think this one could benefit from adding Noun, though, so I'll make sure it's in there!